Bevacizumab, a VEGF-A monoclonal antibody, is used in colorectal cancer. The most clinically significant adverse effect that must be screened for before initiating therapy is:

• A Interstitial pneumonitis requiring pulmonary function tests
• B Infusion-related anaphylaxis requiring premedication with antihistamines
• C Impaired wound healing and risk of GI perforation ✓
• D Tumor lysis syndrome requiring allopurinol prophylaxis

Explanation

Bevacizumab inhibits VEGF-A, reducing angiogenesis and impairing wound healing. Because VEGF is essential for normal wound repair and maintenance of mucosal integrity, bevacizumab use is associated with impaired surgical wound healing, anastomotic dehiscence, and—most seriously—spontaneous GI perforation (1–3% risk). Bevacizumab must be withheld at least 6–8 weeks before elective surgery and not restarted until the wound is fully healed. Hypertension (due to reduced nitric oxide from anti-VEGF effects on endothelium) and proteinuria (due to reduced VEGF in glomerular endothelium) are other characteristic toxicities. Tumor lysis syndrome is not associated with bevacizumab.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.